1. Field of the Invention
This invention relates to a system for measuring distances and trajectories of people or objects traveled in sports activities, such as athletics or golf.
2. Description of the Related Art
With reference, for example, to the athletic events of shot putting, discus, hammer and javelin throwing, long jump and triple jump, a body (defined by an implement, such as the discus, or by the athlete himself) undergoes a substantially parabolic flight between a take-off area and a landing area. The flight take-off area can be a take-off board positioned at the end of an acceleration path (as in the case of the long jump and triple jump, in which at one end of this board there is a band of yieldable material or plasticine indicator), a board, for example of circular shape (as for hammer throwing), or an acceleration track bounded by a non-passable edge (as for javelin throwing). The landing area is provided on a surface the extent of which varies according to the type of athletics event, such surface being either compact (such as for the landing of an implement) or yieldable, with sand (such as the usual pit used in the long or triple jump).
After the body has landed, the distance between the point of impact and the point of take-off is measured to determine the propelled distance for the body and suitably displayed on an appropriate known display unit.
Depending on the type of propulsion (throw or jump), such measurement can be effected principally with two different instruments, namely a tape measure or a theodolite. However, the use of these measuring devices involves various problems. For example, measurement by a tape measure is not precise because of the instability of the tape measure, which tends to become twisted. There is hence a loss of linearity of the tape measure and the possibility of an incorrect measurement.
Even though the use of a theodolite (for example a tachometer) enables more accurate measurement, it does not guarantee exact precision. Its use requires positioning a measurement member, for example an electronic tachometer, outside the landing surface, and positioning a reflecting element within it. The distance that the body has been thrown or has jumped is measured by triangulation between the landing point, the tachometer position point, and the starting point (which can be arbitrary or virtual, such as the center of the shot putting board) of the body undergoing the trajectory.
This measurement may, however, not be absolutely correct. In this respect, the use of this instrument requires a reflector element to be positioned exactly at the impact mark, and maintained perfectly perpendicular to the landing surface. In addition using a theodolite with a reflecting element positioned on a yieldable surface (of sand) inevitably makes it difficult to obtain and maintain the correct measurement position. The use of a theodolite also device that the competition judge making the measurement must be trained in its use. The instrument is also expensive. Finally, the instrument must be reset after each group of jumps or throws.
An object of this invention is therefore to provide a system for correctly measuring the propelled distance of a body in a sports event in which the body follows an aerial trajectory between a take-off area and a landing area, and immediately displaying the measured value on termination of the trajectory.
A further object is to enable the trajectory to be verified three-dimensionally after its termination, in order, for example, to enable it to be described or be compared with other previous trajectories or with an ideal trajectory.
A further object is to provide a system of the stated type that provides constant results, which always provides correct measurements, and which requires no specialization by personnel (event judges) controlling the progress of the competition.
A further object is to provide a system of the stated type that can be used in any event, in which a body (athlete or sports implement) jumps or is thrown (through an aerial trajectory).
The present invention measures the distance and trajectory traveled by bodies in flight during sports events such as athletics, for example a shot, a discus or javelin, or the athlete himself when executing a long jump. The bodies executing trajectories having a common predetermined take-off area, and a landing point variable within a landing surface.
The system of the present invention includes a fixed image acquisition device, such as a video camera for acquiring the image of the landing surface and positioned at a predetermined distance from the take-off area. Also included is a recorder, such as a digital recorder, for recording the image or the body in flight, at least from the moment of initiation of the flight to its completion. The present invention further includes a device for identifying the landing point of the body within the landing surface. This device may be, for example, a cursor movable on a calculation area matrix present on a monitor. The cursor can be positioned on the landing point of the body that has undergone the aerial trajectory.
The system of the present invention further includes a calculating device, such as a microprocessor, for calculating the distance of the landing point from the take-off area. Preferably, a display unit displays the result of the distance calculation.
Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings.